介绍了用离散型随机变量的二项分布函数从试题库随机选题的数学模型。
This paper introduces the mathematical model for dynamically choosing questions from the question database by using binary distributed function with random variables.
张老师建议大家从网站下载一些试题，然后每天坚持练习。
Zhang's advice is to download some tests from the website, and try to practice every day.
有人会认为我是在推销自己的模测题，但是事实是：泰德的托福网考模测试题是从2002年开始研发的，完全是在ETS的核心技术和核心资源支持下做的。
It may seem that I am trying to do the promotion. The fact is that the development of Tide's simulated tests initiated in 2002 with the support of est's core technology and resource.
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